TRENTON, N.J. - New Jersey Gov. Chris Christie's long-time press secretary is set to tell a state legislative committee what he knew about a political retribution plot carried out by former aides to the governor.

Michael Drewniak is scheduled to testify under oath Tuesday.

The panel is investigating the intentional blocking of traffic near the George Washington Bridge last September to retaliate against the mayor of Fort Lee, the town at the base of the busy span.

Christie has denied knowledge of the planning or execution of the plot that has become a major distraction as the Republican contemplates a 2016 run for president.

The scheme has been blamed on former aides in the governor's office and at the Port Authority of New York and New Jersey, the agency that operates the bridge.